System and method for dispenser control

Abstract

Applicators and methods for dispensing material are disclosed. The applicator includes a syringe defining an inlet, and outlet, a chamber extending from the inlet to the outlet, a plunger disposed within the chamber, and a piston attached to the plunger, where the piston is configured to move the plunger through the chamber. The applicator also includes an actuation mechanism configured to linearly translate the piston through the chamber so as to dispense material through the outlet, a sensor attached to the plunger, where the sensor is configured to sense a linear movement of the plunger, and a controller configured to adjust operation of the actuation mechanism based on the linear movement sensed by the sensor such that the piston repeatedly dispenses a predetermined amount of the material from the outlet of the syringe over a plurality of dispense cycles.

What is claimed is: 
     
       1. An applicator for dispensing material, the applicator comprising:
 a syringe defining an inlet, an outlet, and a chamber extending from the inlet to the outlet; 
 a piston disposed within the chamber; 
 a plunger attached to the piston, wherein the piston is configured to move with the plunger through the chamber; 
 an actuation mechanism configured to linearly translate the piston through the chamber so as to dispense material through the outlet; 
 a sensor attached to the plunger, wherein the sensor is configured to sense a plurality of linear movements of the plunger; and 
 a controller configured to adjust operation of the actuation mechanism based on an average magnitude of the plurality of linear movements sensed by the sensor during respective ones of a plurality of dispense cycles, such that the piston repeatedly dispenses a predetermined amount of the material from the outlet of the syringe over the plurality of dispense cycles. 
 
     
     
       2. The applicator of  claim 1 , wherein the plurality of dispense cycles comprises 50 dispense cycles. 
     
     
       3. The applicator of  claim 1 , wherein the controller includes a human-machine interface configured to receive a user input that determines a quantity for the plurality of dispense cycles. 
     
     
       4. The applicator of  claim 1 , wherein the average magnitude of the plurality of linear movements is a moving average, such that the average magnitude of the plurality of linear movements at any time is an average magnitude of an immediately preceding plurality of linear movements. 
     
     
       5. The applicator of  claim 1 , wherein the controller is configured to adjust operation of the actuation mechanism when the linear movement is outside a predetermined range. 
     
     
       6. The applicator of  claim 1 , wherein the sensor is a linear position transducer. 
     
     
       7. The applicator of  claim 1 , wherein the controller is configured to adjust operation of the actuation mechanism automatically. 
     
     
       8. The applicator of  claim 1 , wherein the controller includes an amplifier configured to process a signal that is indicative of the linear movement. 
     
     
       9. The applicator of  claim 1 , wherein the controller is configured to track a total linear movement of the plunger through the chamber. 
     
     
       10. The applicator of  claim 1 , further comprising:
 a valve assembly including a valve seat and a needle configured to translate between a first position, where the needle is spaced from the valve seat, and a second position, where the needle contacts the valve seat, in a dispensing operation for jetting material from the valve assembly; and 
 a piezoelectric device for moving the needle in response to receiving a voltage, 
 wherein the syringe is configured to provide the material to the valve assembly. 
 
     
     
       11. The applicator of  claim 1 , wherein the actuation mechanism is a pneumatic actuator. 
     
     
       12. A method of dispensing material from a syringe, the method comprising:
 operating an actuation mechanism to linearly translate a piston and a plunger attached thereto through a chamber of the syringe so as to dispense material through an outlet of the syringe; 
 sensing a plurality of linear movements of the plunger via a sensor; 
 calculating an average magnitude of the plurality of linear movements during respective ones of a plurality of dispense cycles; and 
 adjusting operation of the actuation mechanism based on the average magnitude of the plurality of linear movements sensed by the sensor such that the piston repeatedly dispenses a predetermined amount of the material from the outlet of the syringe over the plurality of dispense cycles. 
 
     
     
       13. The method of  claim 12 , wherein the plurality of dispense cycles comprises 50 dispense cycles. 
     
     
       14. The method of  claim 12 , further comprising:
 recalculating the average magnitude of the plurality of linear movements at regular intervals, such that the average magnitude of the plurality of linear movements at any time is an average magnitude of an immediately preceding plurality of linear movements. 
 
     
     
       15. The method of  claim 12 , wherein the adjusting operation of the actuation mechanism comprises adjusting the operation of the actuation mechanism when the linear movement is outside a predetermined range. 
     
     
       16. The method of  claim 12 , wherein adjusting the operation of the actuation mechanism comprises automatically adjusting the operation of the actuation mechanism via a controller. 
     
     
       17. The method of  claim 12 , further comprising:
 transmitting a signal indicative of the linear movement to a controller; and 
 amplifying the signal. 
 
     
     
       18. The method of  claim 12 , further comprising:
 tracking a total linear movement of the plunger through the chamber. 
 
     
     
       19. The method of  claim 12 , wherein the piston progressively advances through the chamber along a first direction over the plurality of dispense cycles, whereby each linear movement of the plurality of linear movements of the plunger is along the first direction. 
     
     
       20. The applicator of  claim 1 , wherein the piston is configured to progressively advance through the chamber along a first direction over the plurality of dispense cycles, whereby each linear movement of the plurality of linear movements of the plunger is along the first direction.